Sort the data before operate the macro.

Sub Pagebreak()

ActiveSheet.ResetAllPageBreaks  'Clear existing page breaks

Dim Rng As Range    'number of rows
Dim lngCOL As Long   'column number to use - user input
Dim lngROW As Long    'row count

On Error GoTo EndMacro
Application.ScreenUpdating = False

lngCOL = InputBox("Enter the column NUMBER to use", "Column page break")

Set Rng = ActiveSheet.UsedRange.Rows

For lngROW =  3  To Rng.Rows.Count  'start by comparing row 2 and 3
  If Cells(lngROW, lngCOL).Formula <> Cells(lngROW -  1 , lngCOL).Formula Then
      ActiveWindow.SelectedSheets.HPageBreaks.Add Before:=Cells(lngROW, lngCOL)
      Application.StatusBar = "Row: " + Format(lngROW)
  End If
Next lngROW
Application.StatusBar = "Done"

EndMacro:
Set Rng = Nothing
Application.ScreenUpdating = True

End Sub